This antique skull and crossbones symbol was once used to mark poison. Bettmann / Getty Images

Nowadays U.S. grocery shoppers can be reasonably certain that the foods they purchase are safe (if not healthy). But this wasn't always the case. In fact, if it wasn't for one extremely driven, imperfect man on a mission to clean up America's food industry we might well still have rampant contamination in the grocery aisles today. Harvey Wiley didn't think it was enough to conduct conventional safety studies, either -- he jumped straight to human experimentation. Join the guys as they delve into the strange story of Harvey Wiley and the Poison Squad.